The long term objective is to develop an anesthesia delivery system with monitoring, alarm and control capabilities so that 1) closed circuit anesthesia can be performed as easily as the semi-closed high flow procedure presently is and 2) the anesthesiologist's awareness of the state of the anesthesia and the anesthesia equipment is improved for both the closed circuit and semi-closed high flow procedures. The specific aims are: 1) develop a digital valve/vaporizer system for precision delivery of anesthetic gas, 2) design and implement a microcomputer based control system for automatic control of inspiratory anesthetic gas concentration and 3) develop an intelligent alarm system for detection of anesthesia alarm states. During Phase II a prototype of the valve vaporizer will be constructed and tested in the animal laboratory at Standard University under the direction of Dr. Charles Wittcher. Following any necessary design changes required for clinical application, the steps required to obtain approval for use in humans will be performed and development of the intelligent anesthesia alarm system will begin.